The dangers of climate change are not usually couched in terms of national security, but awareness of the issue is growing rapidly. What could be more basic to security than a climate conducive for agriculture, abundant water supplies, ecosystem health, industrial production, biodiversity, and human comfort? What could be more threatening than extreme weather events or mass migrations because of rising seas and crop failures? The annual ELI-Miriam Hamilton Keare Policy Forum brought together top experts on the topic.